Incidence and outcome of hepatic veno-occlusive disease after blood or marrow transplantation: a prospective cohort study of the European Group for Blood and Marrow Transplantation. European Group for Blood and Marrow Transplantation Chronic Leukemia Working Party

To determine the incidence and outcome of hepatic veno-occlusive disease (VOD) after blood or marrow transplantation (BMT), we prospectively evaluated all consecutive patients receiving a BMT during a 6-month period in participating EBMT centers. All of them were evaluated for occurrence of VOD according to previously defined clinical criteria. The clinical course, outcome, value of prophylactic and therapeutic interventions, and the influence of previously described risk factors were analyzed. During the study period, 1,652 BMT were performed in 73 centers. VOD was diagnosed in 87 patients (5.3%; 95% confidence interval [CI], 4.2% to 6.4%). Fifty-six of 631 allogeneic BMT (8.9%) and 31 of 1,010 autologous BMT (3.1%) developed this complication (P <.0001). VOD was classified as mild in 7 (8%), moderate in 56 (64.4%), and severe in 24 (27.6%) cases. Sixteen patients died of VOD (corresponding to 1% of the whole series, 18.4% of VOD patients, and 66.7% of severe VOD). The use of unfractionated heparin did not significantly decrease the incidence of VOD. Independent variables associated with an increased risk of VOD were allogeneic BMT (relative risk [RR], 2.8; P <.001), pre-BMT elevation of serum aspartate aminotransferase (RR, 2.4; P =.001), high-dose cytoreductive therapy (RR, 2.3; P =.003), Karnofsky performance score less than 90% (RR, 2.7; P =.006), and prior abdominal radiation (RR, 2.9; P =.03). In conclusion, this prospective study shows that (1) the incidence of VOD is lower than that reported in smaller studies from single centers, (2) about one fourth of cases of VOD progress to severe disease, (3) main risk factors have a major impact on incidence of VOD, and (4) the use of prophylactic unfractionated heparin does not seem to reduce the incidence of VOD.     

OMVPE grown GalnAs: C for HBTs

We have grown GaInAs:C by low pressure organometallic vapor phase epitaxy and observed that the hole concentration of such layers decreases upon growth of cap layers such as heterojunction bipolar transistor emitter layers. Two mechanisms were found to play a role: one is H repassivation of the C_As acceptors, the other a non-H related decrease in the concentration of C_As acceptors due to C changing site or to the formation of complexes involving C_As. Depending on the growth conditions of the cap layers (temperature, flow of group V sources), one or the other mechanism prevails.     

Preparation of polystyrene resin with pendant vicinal dioxime groups

Preparation of macroporous polystyrene beads having pendant vicinal dioxime groups and their metal chelating ability is described. Acetylated polystyrene resin crosslinked with 2 mol-% divinyl benzene was oxidized with SeO₂ to give the polymer bearing glyoxyloyl side groups. Then, treating with hydroxylamine, the polymer possessing dioxime groups was obtained. Metal absorbtivity and decomplexation of the resulting polymeric resin were investigated in a wide pH range.     

Multigigabit/s 1.5 μm λ/4-shifted DFB OEIC transmitterand its use in transmission experiments

Optoelectronic integrated circuit (OEIC) transmitters consisting of 1.5 μm λ/4-shifted distributed feedback (DFB) lasers and InGaAs-InAlAs MODFETs were fabricated for the first time. The entire processing requires only two organometallic vapor-phase epitaxy (OMVPE) growths, with the potential for high yield and low cost. Direct modulation of the OEIC transmitter is demonstrated for bit rates up to 10 Gb/s. A transmission experiment using the OEIC transmitter and a hybrid p-i-n/HEMT receiver is conducted at 5 Gb/s, with a sensitivity of -20 dBm and a bit-rate-distance product of 145 Gb/s-km     

Waveguide integrated MSM photodetector on InP

An interdigitated metal-semiconductor-metal Schottky barrier photodetector monolithically integrated with a ridge waveguide and suitable for the 1.3-1.6 μm wavelength range is reported. The GaInAs detector on top of a GaInAsP (Λ_g=1.2 μm) guide used a 35 nm layer of GaAs to enhance the Schottky barrier. Internal quantum efficiencies of around 80% and a pulse response of 147 ps (FWHM) were obtained     

1.5 μm GaInAsP angled-facet flared-waveguide traveling-wavelaser amplifiers

A broadband laser amplifier requires extremely low facet reflectivity (<0.1%). Previously, a low effective facet reflectivity of 0.05% was realized by an angle-facet structure in the 1.3-μm wavelength band. Present work reports an improved structure for the 1.5-μm wavelength band by flaring the waveguide ends near the angled facets. With a conventional antireflection coating of ~1% reflectivity, the measured effective facet reflectivity is less than 0.01% and the resultant devices have a fiber-to-fiber gain of 15 dB centered at 1.49 μm     

Calculating the maximum execution time of real-time programs

In real-time systems, the timing behavior is an important property of each task. It has to be guaranteed that the execution of a task does not take longer than the specified amount of time. Thus, a knowledge about the maximum execution time of programs is of utmost importance.This paper discusses the problems for the calculation of the maximum execution time (MAXT... MAximum eXecution Time). It shows the preconditions which have to be met before the MAXT of a task can be calculated. Rules for the MAXT calculation are described. Triggered by the observation that in most cases the calculated MAXT far exceeds the actual execution time, new language constructs are introduced. These constructs allow programmers to put into their programs more information about the behavior of the algorithms implemented and help to improve the self checking property of programs. As a consequence, the quality of MAXT calculations is improved significantly. In a realistic example, an improvement fator of 11 has been achieved.     

Monolithically integrated 1 × 12 array of planar InGaAs/InP photodiodes

We describe the fabrication and performance of monolithically integrated, 1 × 12 arrays of InGaAs/InP p-i-n photodiodes. These devices are completely optically and electrically interfaced for use in fiber-optic systems. For each element of the array, at -5 V, the dark current is <20 nA, and the total capacitance is <2.5 pF. The external coupling efficiency at 1.3 μm is >75 percent for every diode in the array. We have also measured the coupling capacitance between adjacent devices, and found it to be <0.1 pF.     

Automated synthesis of analog electrical circuits by means ofgenetic programming

Analog circuit synthesis entails the creation of both the topology and the sizing (numerical values) of all of the circuit's components. This paper presents a single uniform approach using genetic programming for the automatic synthesis of both the topology and sizing of a suite of eight different prototypical analog circuits, including a low-pass filter, a crossover filter, a source identification circuit, an amplifier, a computational circuit, a time-optimal controller circuit, a temperature-sensing circuit, and a voltage reference circuit. The problem-specific information required for each of the eight problems is minimal and consists of the number of inputs and outputs of the desired circuit, the types of available components, and a fitness measure that restates the high-level statement of the circuit's desired behavior as a measurable mathematical quantity. The eight genetically evolved circuits constitute an instance of an evolutionary computation technique producing results on a task that is usually thought of as requiring human intelligence     

Metal chelating resins by condensation of ethylene diamine with p-dichloromethyl benzene

Polycondensation of ethylene diamine with p-dichloromethyl benzene in different molar ratios (0.8–1.5) gives mostly crosslinked polymers. These resinous polymers are water-compatible and have moderate swelling ability (swelling rate 1.6–20) in water depending on the pH of the solutions. The free amine state of the resinous polymers are capable of chelating with various transition-metal ions such as Cu(II), Ni(II), Co(II), Cd(II), and Zn(II), even in very low concentrations. Due to rapid complexation, high metal binding capacity, and ease of regenerability, these resins can be useful for the removal and recovery of transition-metal ions from water solutions. © 1996 John Wiley & Sons, Inc.